Monkey
by Nightwind
Summary: Without him, I was nothing. Without me, he was a monster. Sideswipe and Sunstreaker, Nightwind style.
1. Chapter 1

_I warn you up front that these are __**NOT**__ the fanon happy, stupid, pranking Lambos. In fact, if you love those Lambos and don't want to see them in any other way, you will hate my interpretation of them and you'd be well advised not to read this. Skippity-skip! Off with you! :) But I, taking something mentioned in his original official profile to something of an extreme, rather like the idea of a __**truly**__ sociopathic but still "good guy" Sunstreaker, and I simply want to explore the concept a bit. _

_There is more of this story, two more chapters; I'm just uncertain as to whether or not anyone would want to read them. If you do find yourself wanting to read more, do let me know. I'll warn you that it's dark, likely a product of the rather deep depression that's been plaguing me for about the past two years, and it does not end very happily. (No, this isn't a plea for reviews. I really don't care about reviews. You can just PM me with the word "more," if you like. :) It's simply that if there's no interest, I'll leave this as a one-shot and not subject y'all to Teh Dark. I'll keep it all to myself instead, and/or maybe post the rest on my fic LJ if the mood strikes.)_

_Also, if any of you is at all familiar with the first few episodes of the original _Star Trek_ TV series, you might just recognize from whence my inspiration for my interpretation of the "twins" comes…_

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He jolted me from a sound slumber, a bright and vicious glee that wasn't mine flaring deeply and disturbingly in my spark, streaming over my consciousness in a cold and uncontrollable flood that unceremoniously yanked me from my blessed near-unconsciousness. I jerked upright as the emotion swallowed me whole, forgetting as I always did that his bunk is above mine and, as always, my head collided with the bottom of it with a ringing, reverberating clang. There was pain from the collision, but for the moment it felt distant. Immaterial. Unreal.

All that was real was the glee. The glee was dangerous, powerfully dangerous, perhaps the most dangerous thing in the universe. Because when he felt glee like this that was twitching and tingling through me, it meant that something very bad was happening to someone else, and there was nothing that I could do about it. I could only sit there on my bunk in oppressive darkness that weighed on me as if it was some tangible, physical thing, with my head ringing and the horrible glee pouring through me, infiltrating me, sickening me. I shivered. I shivered with dread and with fear and with deep compassion for whoever was on the receiving end of his fury and its accompanying awful, sadistic _happiness_. Even if that individual was a Decepticon.

I prayed, prayed fervently there in the cold, suffocating darkness, that it _was_ a Decepticon. I hadn't heard any alarm klaxons which would indicate that any Decepticons were in the general vicinity or that they were up to something somewhere else, but that wasn't necessarily surprising. I slept deeply, like the dead, because it was my only escape from him, temporary though it was. So maybe there was a battle going on somewhere. I hoped that there was. I prayed that there was because that meant that the receptacle of his awful glee was most likely a Decepticon.

I dreaded the day when one of the Autobots stranded here with us would become his source of glee. Or worse, if…_when_ it would be a human. I knew that the humans annoyed him deeply, that he thought them far below any kind of contempt. He thought this even of those humans who were our friends and who practically lived here amongst us, who had on occasion saved at least some of our lives. I knew that he didn't trust them, any of them, which wasn't surprising since he trusted no one except for me. And even that trust was tenuous and vague at best, and he would vehemently deny that he possessed it, if anyone happened to ask him.

And the humans were so fragile. Easy to break. Easy to crush, and there had been a rather fearfully large number of instances when he had wanted, _desperately_ wanted, to crush one of them. Longing, frantic thoughts accompanied by clear, horrible visions of the act would run through him and thus through me as well, flowing strongly and horribly and so very casually through his mind and his spark, forcefully invading mine while it did so. He always focused on the notion that he could pick a human up and slowly crush them while they screamed and screamed and begged for mercy…until they stopped screaming and begging and all that was left of them was a small mass of pulpy, bloody goo in his hand. He thought that it would be so easy, so…fun, in an experimental, new-experience sort of way.

It was only the thought of the goo that, so far, had stayed him from following through on these thoughts that would occur to him, that would suddenly leap upon him whenever one of them said or did something that even mildly annoyed him. As much as he was often chided and teased for his vanity – No one knew that they were playing with serious fire when they did that – I knew that _everyone_ should be deliriously happy that it existed. I often wanted to shout it from the rafters that everyone should be happy that he was vain, that he abhorred mess, particularly so when it came to mess on his own person. _I_ was certainly happy that he was so fastidious. Because if he ever followed through on his thoughts regarding the humans…

Beating on a fellow Autobot was somehow excusable, so long as no one was killed. Or at least excuses had always been found in the past. He could conjure them out of nothing like the most brilliant and dazzling of sorcerers. And he could be very charming when he wanted to be, which was whenever it suited his purposes. He could be so charming that people believed even the weakest and flimsiest of excuses that he offered, because they wanted to believe them. They wanted to believe that a body so physically beautiful could not possibly house a dark and depraved spark. The notion that startling beauty and utter depravity could coexist in a single individual was somehow anathema.

So, time after time he'd been forgiven, his excuses believed, his charm nailing its target dead-center as it always did. Perhaps he was forgiven partly for my sake. I was the innocent, good-natured "brother" that everyone liked, and this notion added to the ever-growing burden of guilt that I carry. After he'd been forgiven and given the "last" chance that he always so earnestly pleaded for, he'd simply been separated from his properly-compensated victim. But such separation isn't possible here on Earth, stuck as we are. And if he ever harmed a human…Well, there would be no acceptable excuse for that, at least not in Optimus Prime's eyes. And then…

And then the secret would be out. Or at least it would be much closer to being out.

The secret is that we aren't twins, although that is what we tell people. That is the story that he created for us, for he is talented at creating complex webs of lies, and we had connections that could make this particular web that he constructed "official." So that is what everyone believes, that is what is in our official records, and so the things that he has done have not so far tainted me because no one suspects the truth. So, we tell everyone the twin story because it's easier than the truth. More believable than the truth. Less terrifying than the truth.

Because the truth is that we are one person. One person living in two bodies. And that one person was once a murderer. A serial killer, to be specific. A successful one, such as success is measured in sociopath circles, with a long string of victims so very carefully chosen for certain characteristics that the authorities had never been able to connect but that were entirely and eminently obvious and logical to the me-that-became-an-us.

But I had slipped up. Once. Once was all the opportunity that the authorities had needed. Caught, tried, found guilty, and sentenced to death for my crimes, I had been offered a last-minute alternative to termination. An experimental procedure conjured by some bleeding-heart individual who was opposed to terminating for society's own good hopelessly, irredeemably twisted monsters like me. The procedure was supposedly designed to purge the darkness from individuals like me, and it had supposedly been, according to the terribly, meekly earnest person who had offered the option to me, successful on a few occasions. And if it wasn't successful, it would simply kill me. Since I was scheduled to die a few days hence anyway, I figured that I had very little to lose.

At the time, I had wanted to live, after all.

Only it hadn't worked…but neither had I, either of us, died. Instead, my single spark had been split in two, each of the halves retaining some characteristics of the original, whole, individual. Bodies were hurriedly constructed or somehow acquired - I didn't know and didn't care which – lest the two half-sparks fade. The bodies were of similar design, making the twin story even easier to propagate.

It was only after we had each settled into one of the bodies that it was discovered that the darkness was still very much alive and well in him, but _only_ in him. Yet, it was not as effective as it had been because he now lacked some key serial killer qualities that had ended up as part of me. He had the hair-trigger temper and the intentions and the deeply-seated, driving, obsessive compulsions that urged him to pick up right where we had left off. But he now lacked the planning capabilities, the assessment skills, the deceptively happy charisma, and perhaps the intelligence necessary to be successful on the dark, macabre path of the sociopathic serial killer. Those qualities were all in me…only I found myself lacking the violence and the compulsions and what-have-you. It has ever since been a struggle to find a useful, non-sociopathic purpose for the qualities that I have. Now that they are untainted by darker desires and motivations, I don't really know what to do with them.

I am…incomplete. And so is he. But what we were when we were complete was…horrible. I see that now, and the guilt of it gnaws at me. I retain a complete set of memories, and they horrify me. Every image convicts me, condemns me, and I do crazy things to distract myself from them, to separate myself from them, from him. I do what I can to make amends for the things that I have done. But he…He _yearns_ to be again what we once were, and it frustrates him that he can't be, not by himself. And it frustrates him, too, that I don't want to return to that life. Never. It frustrates him so much that I think that he would kill me, if not for the nagging thought that in killing me he might also destroy himself.

So he is literally my other half. My darker half. My _stronger_ half, really. Without him, I am nothing. Weak, ineffectual, often lacking in confidence and completely lacking in purpose. Without me, he is…a monster, a crazed creature of complete darkness who knows no restraint, much less any limits.

When it had all happened, after it was done, I was told that I was the lucky one, that I was forever free of the darkness and its relentless compulsions, that I was now "normal." But I wasn't free of those things because as it turned out, I wasn't free of _him_. There was this connection between us, not unlike that which exists between bonded individuals, that they hadn't anticipated, that had never happened before in their few previous trials of the procedure that we had undergone because the procedure had never before split a spark in two and had both halves subsequently survive in the aftermath. And because of the connection between us, they couldn't destroy him because they feared that doing so would also destroy me. Although no one was really sure about that. No one could or would be sure about that until one of us died.

And no one – except me, at the time, and even sometimes now – wanted me, the "good twin," to be destroyed. So I kept him in check. I keep him in check to the best of my ability now, for that has become my purpose in life. I give him the restraint that he lacks, and I try to deflect and blunt the darkest of his thoughts and compulsions and desires through the connection – the bond, although that word leaves a bad taste in my mouth – between us. Sometimes, I can draw strength of character and resolve and self-confidence from him in return, qualities that I no longer possess myself, that are now a part of him. But more often than not, he gives nothing in return. He only takes, and it is deeply, painfully draining. So sometimes, more and more often lately, I escape from him via the only avenue open to me: Drugged, dreamless sleep that is very near to comatose unconsciousness, very near to death itself but not _quite_ at that blessed place of release, of true freedom. Not yet.

Sometimes I want to die, but it's a selfish want, one which guilt stays me from bringing about myself. Were I to die, if my death will not also bring about his, there would be no one who could possibly control or contain him. And I don't want the results of that on my conscience, just in case there really is some sort of afterlife. So if I were ever to kill myself, I know that I will have to kill him, too, just to be sure that he will die, too. And I can only hope that if I die in some battle that the same battle will take him as well and at more or less the same time. Because if he were to live on after my death…I shuddered at the thought.

Still, if there is an afterlife, and I bring him into it with me, it has often occurred to me that I might still find myself connected to him. He might very well be an _eternal_ monkey on my back, not just one that plagues me now. The thought as it ran through my mind again was vaguely horrifying, as it always was…

And then the doorchime rang, indicating that someone wanted me to open it. Consulting my internal chronometer, I noted that the hour was such that no one should be bothering me. Unless, of course…Cold dread gripped me then, conflicting with and hammering against the glee that he was still feeling and that was still projecting strongly onto me, and I swung my legs mechanically off of my bunk. I moved toward the door without thinking about it at all, pressed the control, and the door between my visitor and me slid aside with a soft, airy hiss.

Prowl was there. His face was placid. It was always placid, at least on the surface, and the surface is all that most people ever see of anyone. But I am a deeply observant individual, very near to empathic if not actually all the way there. It's a characteristic that I had always used before, before the fracturing of my spark, when I had been choosing a victim. It's a characteristic that had allowed me to revel, horribly, in the suffering of my prey. It's a characteristic that I solely possess now, and this frustrates him, takes away some of his joy but not the glee. Never the terrible glee.

Looking at Prowl now, sizing him up in a practiced, thoughtless instant, I knew that the placid exterior was currently – and only barely – masking a deep, seething fury. I could almost smell anger rising from him. The blue eyes before me, level with mine, were practically blazing with it, a cold fire that anyone could see if they knew how to see at all, if they knew how to _really_ see. But not many people have the ability to really see, to be able to read the entirety of a person, even the things they don't want you to know, in the way that normal people read books.

Most people think Prowl cold and emotionless, mostly because he wants them to think that. It is the insulating image that he projects, the method that he uses to keep people at bay so that they don't approach and possibly breach his fragile defenses. It is the surface layer of him, the thin outer skin of the many-layered onion that is Prowl. Had I known Prowl before, before the split, I should have liked to have peeled through those layers of his, slowly and carefully and methodically, until I arrived at his innermost layer, at his true, naked self. He would have been a target, perhaps the ultimate one, the bright and glorious culmination of my long career.

But now…Although I could remember the desire, how it felt, how it had utterly consumed me, the desire simply wasn't there in me anymore. It was his, all his. And I was _constantly_ pulling him away from Prowl, away from deep and dark thoughts of Prowl, away from fumbling, ill-conceived plans that entirely lacked in finesse and that all centered, obsessively, on Prowl.

I had become protective of Prowl that way. I understood him. I kept his secrets and kept my distance from him. And I kept my other half away from him to the best of my ability. And because of that, I know Prowl. Know him better than most. Much better. Prowl's passions run hot and deep and yet secret, and he tries desperately to control them, but he often fails in secret. In private. This, I knew. And I knew that Prowl was furious now. And the dread within me bloomed larger, like a budding black rose unfurling dark and foul-smelling petals. It grew colder and deeper, too, as if it was feeding on Prowl's blazing but hidden anger, as he and I stared at each other for a long moment. Then:

"You need to come with me," was all that Prowl said, was all that he needed to say. His voice was flat, inflectionless, but the flatness reeked to me of deep-seated, all-encompassing fury.

And I knew then. I knew with a clear and brutal certainty that bit into me and then clung tenaciously to me, like a python clinging to its struggling prey as it wraps its thick, unyielding coils around its victim in order to suffocate it.

I knew then that it hadn't been a Decepticon.


	2. Chapter 2

_Ho-leeeee cow! I can't believe the positive response to this story. I am truly, utterly flabbergasted. And completely humbled. I actually wrote much of this story last summer and then kind of chickened out on posting it, fearing fan reaction for totally not complying with the excessively popular fanon version of the twins. And so I lost my drive to complete the story, too. _

_So thank you. Thank from the bottom of my heart to all of you who've read/faved/alerted this story and especially to those of you who took the time to comment on it. Comment responses are below, because I like to do that "in public," when I can, even though it usually ends up getting lengthy. But first, here's the next part of the story._

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His eyes glittered at me from out of the dimness of the cell they'd put him in. Bright, innocent-looking blue eyes. They didn't suit him. They should have been red, eternally enraged red. Like theirs. He belonged with them, really, if he could ever actually belong anywhere. But I didn't belong with them, and we can't be apart. He is my burden to bear, and mine alone, and where I go, he goes. He and the tormenting memories that I carry are my eternal, never-ending penance for my crimes.

He stared at me now, his end of the connection quiet and almost contemplative. Reflective. He was sated for the moment, but only for the moment. _It_ would rise in him again, the dark tide of need, the irresistible compulsion that pulsed hotly through him as human lifeblood flowed through human veins. But for now he lounged, casually, dreadfully casually, on the hard, narrow bunk that folded down from the wall of the cell. One long, golden leg dangled off of the edge of the bunk. His powerful arms were folded behind his flared head, pillowing it on his hands, hands and arms that he would have methodically and fastidiously cleaned until not a single physical trace of his night's handiwork remained.

We had always done that, when he and I had been one. He still did it.

But his head was turned slightly toward me, and there was a wary alertness in him, in his eyes. He'd been watching for me long before I'd arrived, knew of course that I was coming, and now his eyes were fixed on me. Staring eyes. Calm eyes. For now.

I stared back at him for a long moment. And then I asked, voice hushed and careful, "Why?"

We didn't really need to speak verbally, the two of us, two inseparable faces of the same coin. He didn't often speak to me vocally at all, not when were alone, at any rate. He only did so in public, to keep up appearances, and sometimes the words that he said to me and the words that he projected to me were two entirely different things. But I always spoke to him verbally. It was a way to distance myself from him, flimsy though it was, a way to try to forget that we were inseparably linked. The charade offered some comfort where otherwise I had little to none.

He smirked at me, amused as always at my attempt to pretend that we weren't a single person, that our thoughts weren't intertwined and intimately intermingled in such a way that, sometimes, I could not tell if a thought was his or my own. It amused him that I tried to deny that I was as responsible for the things that he did as he was.

_Because I wanted to do it? _came the glib, flippant, lazy, eventual answer to my question of why he had done what he had done. _Because I was bored? Because it was fun? You remember the fun, don't you? You remember how it feels when they scream? You remember the betrayal they feel, the look on their face because they thought you were their friend? You remember what it's like when they beg you to stop but you don't stop, and you just keep going and going until they stop begging because they _can't_ beg anymore? You remember, _brother_. You remember all of it, as I do. Lambs to the slaughter. And you miss it, too, as I do. I _know_ you do._

It was the same old taunting, and he was smug, proud of himself for what he'd done this night. I wanted to spit at him. I wanted to tear open his chest and crush his spark with my own bare hands. He was the _only_ person in the universe that I had any desire to kill now, and the desire amused him deeply. I felt his amusement radiating through him and then through me. He didn't need to mock me for my desire to tear him apart. The amusement was mocking enough, because I was forced to feel it in myself, _about_ myself.

"I don't miss it," I growled at him around a clenched jaw. "And you know it, and it eats at you, eats you alive. You hate it that you need me. That you can't do what you want to do without me when you know that I will never help you. _Never_ again."

He snorted at that, aloud, before delving back into the link between us.

_I don't need you,_ he spat contemptuously. _Why would I need a pathetic weakling like you? You are nothing. That's what you think all the time, isn't it, _dear_ "brother?" And you're right. You're absolutely right. You're nothing. You've been stripped of everything that was ever important. I have all of that, now. And now you disgust me. _He paused, and then finished pointedly, brutally,_ Just as you disgust yourself._

I flinched, involuntarily. Because he was right. Of course he was right. I could keep nothing from him because it's impossible to keep things from yourself. He was right, and I could offer no defense. So I didn't even try. Instead, I changed the subject. It was the only thing I could think to do.

"Why him?" I asked, genuinely, sickly curious. "Did he call you 'Buttercup' again?"

He laughed at that, amused at the question and amused at my feeble attempt to redirect the conversation. His was a warm, rich, mellow laugh, pitched at a perfect, beautiful tenor that was just deep enough to carry easily across a crowded, noisy room. It was a laugh that made people look at him in admiration, in desire. It was part of his whole perfectly attractive package, part of the carefully-designed web in which he – we – ensnared our victims. But it was the worst sound in the universe now, as far as I was concerned. And then he sneered at me, deeply contemptuous as always, as he felt my disgust, felt my deep and utter disapproval of him. He felt that I had no right to judge him. And really, I didn't. He was what he was, and he was me. Sitting in judgment of him was sitting in judgment of myself.

He rolled fluidly, gracefully to a sitting position then, turning as he did so, so that he could lean back against the wall that was then behind him, but his eyes never left mine as he moved. His gaze knifed through me like a sword.

_If you weren't so afraid of me,_ he said simply, _you'd know why. You'd know _exactly_ why._

And he was right again. I was afraid of him, in a sense, afraid to delve too deeply into him, for fear of what I would see, what I would come to know. What I might become under his influence.

_And then you would acknowledge my brilliance. Just as he will, in time._

I narrowed my eyes at him, suspiciously.

"Just as who will?" I asked.

He smiled at me, at the question. His smile might have been beatific, if not for the malice dripping from him. He rose from the bunk, graceful as a cat, and slowly approached the bars that separated us, stopping only when he was so close to them that their energy crackled against him threateningly. He paid it no mind, the entirety of his attention focused solely on me.

"Prowl," he said simply. Quietly. He said it aloud, but he whispered the name reverently, like some sort of macabre prayer.

I jerked away from him and then stumbled backward, farther away from him, my mind reeling. How had I missed this? He didn't want to kill Prowl, didn't want to make of him that sort of victim but rather a victim of an entirely different – and worse – kind. He wanted Prowl as some sort of sick ally or at least as a stripped-down toy whose abilities he could use as we had once used the abilities that I now possess. All this time I'd thought…and I'd been wrong. I backed myself against the wall across from his cell, and I leaned against it as I fought to digest his intentions, as my mind spun crazily, trying to comprehend how I hadn't known of this plan of his long ago.

He laughed again, snickering at my confusion.

_Because although you can't hide your pathetic self and your pathetic thoughts from me,_ he snidely informed me,_ I've learned how to hide from _you_ perfectly well. Because I don't need you, "brother." I need _him_. Only him. I know this now, and I only had to wait for you to drug yourself into oblivion again so that I could start down the road. And now I just have to make him see reason and he will because that's what he does. He's logical and he sees reason and he'll see that he needs me. Certain influences need to be removed first, but – _

"So that's it, then," I interrupted weakly, my mind still flailing around trying to find some sense of balance. "Bluestreak was an 'influence.'"

_Oh yes,_ he answered casually, nodding his head enthusiastically, proudly. He was careless as always, heedless of what he did. There was no guilt in him, for he did not possess the ability to feel such a thing. There was no remorse, either, because that was an utterly foreign concept to him as well. For him, the end justified any means whatsoever, no matter how gruesome.

_I had to nip _that_ one in the bud first thing, _he was happily, cheerfully telling me. _Fragger's practically like a son to him. Blue idolizes him, and I know he'd listen to his whiny babbling instead of listening to me. You understand. I know you do. _

And I did, in a sick, twisted way that I remembered all too well and greatly abhorred.

_Stupid stubborn fragger wouldn't die, though, _he continued with rather revolting airiness_. Like he didn't die when a whole fragging city fell on him. You know the type, I know, because those were always our favorite kind, the ones who lasted for a long, long time. He gave me a most enjoyable fight, too. I know you felt that, and I know you enjoyed it, too, don't try to deny it. And he might as well be dead now, so that will have to be good enough. For now, at least. And then there are just a few others that I will have to deal with, and then…oh, then… It will be glorious, you'll see. Far better than we ever were. He's the best, you know, and I won't settle for less than the best._

I was just staring at him as he babbled blithely away. A jumble of emotions flowed through me as the words, the terrible words, fell from him. His emotions. Mine. Ours. All intermingled. Mostly, though, there was horror. _My_ horror. There was horror at the thought of him slowly and patiently working at Prowl like a cat toying with a mouse, separating him from everything familiar, everything _sane_, and then eating away at him for as long as it took, until there was nothing left but a twisted psyche helpless in the face of a manipulative master like him. And it wouldn't take long; Prowl's defenses were fragile, indeed. And there was horror at the thought that, because I had in a moment of weakness needed a respite from his draining and ever-looming presence, all of this was going to happen. It had already happened to poor Bluestreak, probably the most innocent and undeserving Autobot of them all, and that was my fault. It would happen to whatever others he had plans for, and that would be my fault, too. And it would happen to Prowl, despite my efforts over the years, and the guilt for that would be mine to bear as well.

But then, incongruously and very unexpectedly, the horror gave birth to sudden determination, to strength that I didn't possess, so it must have come from Primus Himself.

"No," I murmured, pushing away from the wall. "No, you're insane."

He laughed again at that. Uproariously. Delightedly.

_That's a _fine_ accusation, coming from you,_ he burbled. _Pot, meet kettle._

"I won't let you do this," I informed him.

Thick waves of deep amusement assaulted me once the words had slipped from my mouth, more cutting than any sword could be.

_And how will you stop me?_ he asked, smirking at me, eyes glittering anew. _I can be out of this cell in less than a minute, if I want to be. You know that. And then I will disappear. And then I will return. And what can you do about any of that?_

"I can tell them," I said firmly, chin rising defiantly, arms crossing over chest.

_Tell them whatever you like, pathetic scrap, _he growled, equally defiantly. _They won't believe you. And even if they do believe you, what will they do? Hmm? Tell me, what will they do? _Before I could answer, he babbled on, loving as always the sound of his own "voice." _Optimus Prime is far nobler than you will ever be, but he is every bit as weak as you are. No wonder he likes you so much. But he won't like you at all once you tell him what you really are, will he, once you tell him what you've done and that you've been lying to him all this time? No one will like you anymore. They'll all be afraid of you, even Prowl, who you've tried so _very_ hard to protect from me that one might think that you were in love with him or something. But he'll be afraid of you now, if you say anything. They'll _all_ be afraid of you. And you can't even _enjoy_ that anymore. You can't even feed on fear the way you used to be able to. You have fallen so very, very far, dear "brother" of mine. And I'm rising. Infuriating, isn't it?_

"Shut up," I said, trying to keep desperation from my voice.

_Why should I?_ he taunted relentlessly back. _I can do this all day, every day, for the rest of your pathetic little life. Won't that be fun?_

"No," I protested, and the desperation was obvious now. I couldn't stop it, couldn't hold it back, certainly couldn't hide it from him. "No no no no no. You won't do this. I will stop you."

I began to sidle away from the cell, away from him. Optimus Prime was likely still in the medbay, still keeping vigil with the others. It was his way. Or he might be in his office. Or in the Control Room. Wherever he was, I would find him. I would find him and tell him. Tell Prowl, too. Apologize to Prowl for what I had allowed him to do to Bluestreak. I would tell them everything, every sordid detail, if that was what it took. I would tell them whatever I had to tell them to make them listen to me, believe me, _do_ something. It was all that was left to me, and if it would damn me as he thought it would, as it probably would, at least it might save Prowl and whomever else he had plans for.

My life in exchange for theirs. It was fitting. Very fitting. It was perhaps the only penance of which I was capable now, since I had ultimately and utterly failed in containing him. It was all that I could offer, now, the only thing I had left to give.

_How very noble of you,_ he snidely called after me as I began to stagger down the corridor, away from him although I could never escape him. _Self sacrifice from the likes of you. What a concept! _

And he laughed, laughed and laughed, aloud as well as in my head. His mocking laughter rang and rang in my head, long after I couldn't hear his out-loud laughing. It chased me as I stumbled blindly down corridor after corridor toward I knew not what. But whatever it was, I could only fervently pray that it would succeed.

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_**Review replies, in no particular order:**_

_**Tiamat**__: Yes, yes, I finally posted it. I'm such a freakin' coward. :) It helped that Sideswipe, after a looooooooooooong absence, decided to pop into my head while I was lightly napping yesterday evening so that I could finally, __**finally**__, finish this second chapter. I guess maybe he likes Anne Rice, since reading one of her novels that I managed to miss when it was published is what gave me the kick to poke at this story again. Anyway, I'm glad that you enjoyed the opening, and I hope that you will like the rest as well._

_**Lokimademedoit**__: Yep, only three chapters all together for this story, although the third one is very long, long enough that it should __**probably**__ be two chapters, and I might make it so. It could be longer, sure, but since this Sunstreaker scares the piss out of me I can't imagine allowing him to roam around in my head for any really long stretch of time. But that doesn't mean that I won't write another story about him/them at some point, after my head has had a chance to recover, if an idea occurs to me. And I'm glad that you got a clear sense of the characters; this piece is mostly meant to be a character piece, and if I hadn't succeeded at that...Well, that would make it a very sucky character piece, indeed. :) I hope that you continue to enjoy the story. _

_**Mrs. Sunstreaker**__: Yep, I can certainly understand preferring a less-dark Sunstreaker! *laughs* 'Cuz this one is scaaaaaary when he lets all his scary hang out, like he sort of did here. But that's kind of the point. I'm a writer who tends to like doing different things, and the bit about "sociopathic tendencies" in Sunstreaker's original official profile has been gnawing away at the back of my brain for years now. _

_**katiesparks**__: Well, no one is purely evil. Even this Sunstreaker has good qualities; they're just sort of twisted and drowned out by psychosis at the moment. But yes, I like reading and creating different interpretations of the characters and really have no idea why some people are so inflexible about that. The fanon twins are fun, but in my opinion they usually lack depth because they're most often played for comedy, and comedy isn't usually about creating character depth. My "twins" are weird and totally not-fun, but at least they have depth! I think. I hope..._

_**Starfire**__: *nods* When I ripped apart the opening the other day, I wanted it to be able to stand alone, in case I chickened out on posting the rest of the story, whether or not people wanted to see it. So yes, ambiguous yet complete. :) It gladdens me that you appreciate my different take on the "twins." It gladdens me that __**anyone**__ appreciates it. :)_

_**Carmilla DeWinter**__: Sideswipe's in a very tough position, yes, much tougher, actually, than Sunstreaker's position. And sometimes death can seem the only way to resolve/escape from such a situation. But in his case, that isn't an option, either. Poor guy. I totally want to hug him…so of course I heap more crap on him instead. *laughs* And…well, as you can see, I've decided to post the rest here, since enough people were interested in it. But the first part's also up on my fic LJ now, too._

_**shadowwriter01**__: It's been said that this fandom can crush originality/creativity, what with some people's insistence on writers adhering to __**fanon**__, of all things, because they've confused fanon with canon. So, posting this was something of an experiment, to see how it would go down, since the fanon twins seem to be so entrenched in the fandom's collective conscious. So far, so good...but then perhaps my warning scared away all those who can't deal with non-fanon twins. I'm glad that you appreciate original ideas...although I can't say that the idea is entirely original. _Star Trek_ did the splitting-one-person-into-two-bodies thing first. :) _

_**Bluebird Soaring**__: Me Nightwind like brilliant part! :D Thank you. :) And yes, there is darkness in all of us...except, oddly enough, in this Sideswipe, now. Darkness has been stripped from him. The thing of it is that, sometimes, it's the darkness that makes us strong, and this is what Sideswipe has discovered…and what he has to overcome. _

_**reaper mendez**__: Your wish is apparently my command, for the rest of it you shall have, for better or worse. I'm glad that you're enjoying it so far._

_**aisling13**__: I think the problem is that most people have no idea what a sociopath is. Unfortunately, I do, having been involved with someone who was at least a borderline sociopath for a few years in my Stupid 20s. This, of course, is informing my Sunstreaker here. So yeah, it's kind of fun in a weird, twisted way to write a truly sociopathic Sunstreaker. I'm glad others are appreciating my attempt._

_**Koyako**__: Sideswipe is described in his original profile as a "daredevil." No mention is made of pranking, specifically, and although I'm not going to write him as a prankster because I'm deliberately separating "my" twins from their fanon selves as much as possible, I can see pranking as an aspect of daredevil-ness, especially risky pranking that could incur serious punishment if he was found out. (I can see Sideswipe, especially "my" Sideswipe here, being very desirous of punishment, actually.) I truly can't see Sunstreaker pranking, though. And I rather like his profile's description of him being contemptuous of Sideswipe __**in particular**__. That works well for my purposes here! :)_

_**Jalaperilo: **__Now that's a very, __**VERY**__ interesting idea that certainly goes against the grain! Sideswipe-as-sociopath. Someone should write that, because everything you said is true and makes all kinds of sense, and it would be such an awesome twist/tweak of what we normally see. I'M not going to write it, though. I like Sideswipe too much to make him a sociopath, whereas I'm not at all fond of Sunstreaker, so twisting and evil-ing him up is totally not a problem for me. *laughs* So I say that __**you**__ should write it. :) But yes. Although I haven't seen many people who've tried to write a sociopath Sunstreaker, those that I have seen seem to fail at least somewhat because it seems they don't know what a sociopath is. I'm attempting to be somewhat authentic, drawing on personal experience with someone who at least flirted with sociopathy (so perhaps that's why this feels "real"), combined with *thunder crash* research. _


	3. Chapter 3

_I've had a couple of people ask me what continuity this story is supposed to be in. So, I thought I'd confirm that it's G1 cartoon, like pretty much all of my stuff. I imagine it being very early on in the series, but I suppose that it doesn't have to be. And I suppose it's slightly AU, since Sunstreaker isn't exactly stark raving loony in the cartoon. :) Still, I arrogantly maintain that "my" Sunstreaker is more canon than the fanon one. ;) But anyway...yeah, that's what it is._

_I must extend my deepest thanks to you all for the continued support for this fic. I thought it would be hated. Shows what I know, eh? Instead, it might just be the most popular thing I've ever written! *laughs* It has broken 50 people having it on alert, and that's utterly amazing, for a story of mine; they often tend to have limited appeal because of what I choose to write about. _

_And I'm very sorry for the delay. I had the best of intentions, but I'm hampered by not having Internet at my new place yet, and work's been pretty crazy because we're preparing to move the office. And I had unexpected house guests for several days. Plus...I needed to tinker with this a bit. I had to split what was the third part in two...because. :) Doing so required a little bit of rewriting in order to create a logical (HAH!) break in it, and my attention kept being pulled away. And then I went and wrote a little epilogue thing. So, this story is in five parts now, and the other two should be up shortly. I just have a little further tinkering to do with the next part which, hopefully, will not take long. _

_My apologies for the lack of review replies this time; I will do them perhaps when I post the next part, or perhaps I will just privately answer everyone. Since you've all waited patiently for this, I don't want to take the time now to write them all. So for now, just know that I am deeply thankful, to all of you, for the positive response that this story has received. So, on to the next part.  
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The two of them were still in the medbay when I arrived there for the second time this very early morning, dawn just breaking outside. They looked at me as I walked in, both gazes immediately crystallizing on me, and they regarded me each with different expressions as they took in my attempt to appear anything other than panicked and half-crazed. To appear calm and sane was a difficult endeavor; Sunstreaker was still laughing and gloating and taunting away in my head. I could do nothing about it, about him, other than doing my level best to ignore him.

Meanwhile, both of them of were regarding me with, amongst other things, a strange combination of sympathetic pity and pained, uncomprehending accusation. I was fairly certain that neither of them had understood my insistence upon seeing Sunstreaker immediately, once I had observed his handiwork, _felt_ his handiwork. I imagined that they had expected me to be as horrified as they were by what my "twin" had done, perhaps even more so because of the "relationship" that they thought existed between Sunstreaker and me. And I _was_ horrified, but for reasons that they could not even begin to suspect. Not yet. Not until I told them.

For his part, Optimus Prime's head was slightly canted to one side as he stared at me, as if I were some perplexing puzzle that he was trying to solve. His expression was always hard to read; his convenient mask concealed everything save his eyes. But I didn't need to see his face. I could read him easily, regardless, always. Optimus Prime hid nothing, likely because he believed that he didn't need to hide anything. The mask was there, his faithful and ever-present shield, and he was entirely unaware that I, at least, could absorb whatever he projected. Usually, he radiated an unimaginable but tightly-contained and controlled power that was tempered with quiet self-confidence and compassion, even with empathy to the extent that being in charge allowed empathy. Empathy unlaced with sadism could be crippling, as I knew all too well, and too much of it was a distinct liability in a leader. It prevented him from making the hard, sometimes brutal decisions that leadership required. But now Optimus Prime was radiating a simple, bleeding confusion more strongly than anything else, and I wasn't quite sure why that would be so.

Our leader certainly knew of Sunstreaker's recent past. It was all in his records, those unfortunate occasions when he'd lost control – Which in reality were the occasions when _I'd_ lost control, when I'd lost track of him – and then something untoward had happened to some unfortunate being, usually the first to cross his path who regarded him in a manner of which he didn't approve. It was all in his records, our records, how we'd been passed around Cybertron as a result of Sunstreaker's actions just before ultimately joining what became an unplanned and unforeseen exodus to Earth. His actions had always been excused because on the one hand he was a master at cultivating undeserved forgiveness but on the other hand because he was, quite simply, a brilliant warrior. He was strong and fearless and supremely capable…and utterly pitiless. He was the best fighter that the Autobots had and the best that most had ever seen or ever would see. So in the war situation in which we were ensnared, Sunstreaker's usefulness always managed to outweigh his "indiscretions." So it shouldn't have been surprising to Prime that Sunstreaker had lost control again. Perhaps it was the utter randomness of the attack that was perturbing him, coupled with the sheer brutality of it; whether or not Bluestreak would survive was very much a matter open to question.

Bluestreak wasn't there in the main ward anymore, and for that I was glad. Neither was Ratchet present, so I assumed that Ratchet was off doing what Ratchet did best: saving lives when they could be saved and sometimes managing to do so even when by all rights success shouldn't have been at all possible. In Bluestreak's case it was likely the latter that was needed. Either way, I had no desire to look upon Bluestreak again as he had been, no desire to see again the shattered wreckage that was ultimately, as ever, my fault.

He'd been battered and terribly broken, bathing and drowning in his own vital fluids, this individual whom I called a friend and whom Sunstreaker had appeared to genuinely tolerate, at least for the most part, which was the very most that could be expected of him. Of all of the damage that had been inflicted upon him, the worst of it to me – because after talking to Sunstreaker I understood why he had done it – was that the components that gave Bluestreak his voice had been torn brutally out of him. Bluestreak's voice was to Sunstreaker the dangerous thing, the one weapon that he believed had the power to derail his carefully-wrought plans. It was the only weapon in Bluestreak's considerable arsenal that Sunstreaker had any reason to fear. It would take time to reconstruct those components, if Bluestreak survived, and time was exactly what Sunstreaker needed. It was the _only_ thing he needed.

And yet somehow, through all of this, Bluestreak had been still conscious when I had last seen him, much less still alive. He'd been in worlds of pain, deep and fathomless oceans of pain. It was the sort of pain that no one should have to suffer and that I had once enjoyed inflicting upon others. Of this, I was brutally reminded as I had gazed upon Bluestreak earlier, as helpless and silent screams that he had no hope of controlling had ripped themselves out of him over and over again. The pain that drove his silent wailing exploded from him and tore at me like a storm of finely-whetted and wind-driven knife blades, each of them lacerating me with guilt. I did not want to face that again, for all that I deserved to face it.

But for all that he was young and vulnerable, Bluestreak was also a contradiction. He was very much a survivor, as strong and as stubbornly determined as they came. An entire city had collapsed on him, not all that long ago if one didn't count the millions of years of stasis, and yet he, in all of his youth and vulnerability, had done what no one else in the city had been able to do: He had _survived_. He had clung doggedly to life until he had been found. Until _Prowl_ had found him.

But he hadn't survived completely intact. I knew this. Bluestreak's damage hovered about him like a black, festering cloud that was almost tangible to me. He sought to dissipate it with bright spirits, happy smiles, and unrelenting and sometimes meaningless chatter, but he could not dispel it completely. It settled over him, enveloping him like a shroud when he was alone, and nightmares were his near-nightly companions. Bluestreak's quarters were close to mine, to ours, and sometimes, if the nightmare was bad enough, strong enough, I could feel its backwash through the distance that separated us. His terror and anguish would batter their way through my fragile defenses, and I could feel full-force the panic that jerked him yelping and sometimes screaming from slumber. His weakness and his brokenness and his desperation and his deep fear of being alone and helpless again were all laid bare before me, almost as if I could reach out and touch them.

All of it ate relentlessly at him and washed over me…and I knew that, at one time, if he had been alive and if I had known him before I was split, I would have savored it all. I would have basked in it as a reptile basks in sunlight, drawing strength from it. And I would have done my best to deepen Bluestreak's brokenness, to magnify and strengthen his fears, slowly and oh so carefully, all without him knowing that I was doing so. I had honed that skill to the level of fine art. It was an art at which I had become a master. It sickened me now.

Yes, I knew why Sunstreaker had chosen Bluestreak, and I knew that it wasn't only because of his strong influence with Prowl. Sunstreaker couldn't feel things in other people as I did anymore – and if anything, the ability was stronger in me now than it had ever been, now that it was wholly unfettered from darkness – but still he knew of Bluestreak's weakness, his vulnerability, his damage, and it attracted him, called siren-like to the darkness that was the whole of his being. He knew of these things because _I_ knew of these things, because I hadn't been able to keep anything from him, not as he had learned to keep things from me. It was one more straw of guilt to heap on the camel's already-straining back, and it enraged me that he had done this to me, that I had handed him the opportunity to do so, all shiny and gift-wrapped. _Again_.

My fury almost equaled Prowl's, in fact. He was standing, leaning back against a wall in a way that would seem casual to any observer other than me. I could sense the undercurrents in him that likely no one else – except, regrettably, Sunstreaker – could imagine existing within him. Gleaming, meticulously-polished black and white doorwings flared against orange wall, his arms were folded neatly beneath his protruding chest, and his expression, as ever, was cool and collected, the façade firmly in place, hiding deep and turbulent depths behind it.

Oh yes, Prowl would be easy, so _very_ easy to twist, if just the right pressure at just the right time was applied to him, oh so carefully. It was easy for me to see why Sunstreaker was drawn to him as if he was an overcharged electromagnet. That I hadn't seen this coming, that I had been so busy protecting Prowl directly that it hadn't even occurred to me that Sunstreaker might try a more oblique approach to him…it tore viciously at me. An utter innocent had suffered horribly for my lack of foresight, for my lack of knowing myself.

Sunstreaker's plan was just the sort of plan that I would have concocted, all those years ago, if a more direct approach had been somehow thwarted. He, of course, had memories of this as well, and even though he might no longer have the capacity to plan for himself like this, he _certainly_ had the ability to mimic the sorts of things that we had done in the past, particularly those things that had been successful. When we had targeted someone for more long-term…amusement, the very first step had always been to isolate the target from friends and family, from anything familiar. This was exactly what Sunstreaker was endeavoring to do to Prowl, now. And he would succeed, I knew, if left unchecked.

And Sunstreaker was right in that Bluestreak was almost like a son to Prowl, that Bluestreak adored Prowl, idolized him, followed him wherever he went, and felt that he owed him his life. And perhaps he did. He had told me once, friend to friend, that Prowl had pulled him from the wreckage, cleaned him up, supported and comforted and guided him, and had eventually given him a purpose in life, one that had turned him away from a path that could so easily have hardened him with hatred and soured him with bitterness. He had learned, under Prowl's tutelage, how to channel his burning, outraged desire for revenge into the very qualities that made him the extremely effective sniper that he was. And the kid was deadly, no doubt about it, with any weapon and at practically any distance. He could kill without a second thought, if he had to, and it was often his duty to do so. But apart from that, Bluestreak was still in many ways an innocent, somehow managing to retain a genuine and almost childlike air about himself. He was…gentle. Supremely likeable.

All of this was to Prowl's credit. Prowl who lived next door to him, now, and deliberately so. Prowl who would come in and comfort him, who would sit with him and talk to him and sometimes even hold him when the nightmares plagued him, when he woke from them screaming for someone, anyone, his the raw, bleeding anguish of an abandoned and terrified child. I knew when Prowl did that, knew the exact moment when he walked into Bluestreak's quarters. The harsh, naked terror that battered at me when the nightmare was particularly bad would mellow the instant that Prowl arrived, and eventually, surprisingly quickly, it would entirely calm, disappear, and usually he was able to sleep again, dreamlessly and painlessly. It was a surprising ability that Prowl harbored, mostly secretly; I doubted that anyone else – other than Sunstreaker, unfortunately – knew about this compassionate and protective side of the stoic tactician.

But Prowl hadn't been able to protect Bluestreak from Sunstreaker, just as I hadn't been able to protect Prowl, not really, and this, perhaps even more than the actual atrocities committed against Bluestreak, infuriated Prowl. And lurking under the fury, intensifying it, was tenacious, clawing guilt that gnawed relentlessly at him. I felt it, the sensations familiar because this was something that he and I had in common, a similar burden that we shared, and I desperately wanted, _needed_, to tell Prowl that. But not yet, not quite yet. First, I had to talk to Optimus Prime, and before I could do that…I had to find the courage to do so.

_Good luck with _that_, you coward,_ the omnipresent voice in mind taunted. The tone was snickering; he'd been listening, of course, to my thoughts, and they were greatly amusing him. _Let me know how it goes, huh? _I had to fight not to snort aloud at that.

Steeling myself, I tore my gaze away from Prowl's penetrating one, and turned toward Optimus Prime's imposing and impressive figure. He was still watching me, just as Prowl was but for different reasons, his gaze still cool and appraising. I approached him slowly, warily, until his shadow fell fully across me, and then I looked up at him nervously.

"May I speak with you, sir?" I asked. Quietly. Deferentially. "Privately," I amended.

He nodded once, silently, and after glancing around himself in search of a suitable location, decided upon Ratchet's office, toward which he then headed decisively. I followed silently in his wake, and I secured the door behind us as I entered the small, cluttered, and, to anyone who wasn't Ratchet, utterly disorganized space.

There wasn't anywhere to sit, so we both stood, the dim lighting positioned and angled such that Prime's shadow still fell across me. I shivered, feeling small. Insignificant.

_Because you are_, his voice taunted merrily, but I ignored him.

Optimus Prime was staring at me expectantly, his minimal visible expression still such that it was obvious that he wasn't sure what to make of me. I pulled in a deep breath, let it out, then pulled in another one. It didn't do much to ease me, and I had no idea what to say, now that the moment to say _something_ had arrived.

_Not surprising_, the voice scathingly said. _Idiot. I got all the brains._

I scowled, only barely managing not to answer the voice aloud, and then I determinedly told myself not to listen to him. Instead, I lifted my gaze to focus on Prime, who if anything appeared more confused. It wasn't surprising, given that I was acting strangely.

"There's something I need to tell you," I said without thinking about it, the words falling out of my mouth before I'd even really thought about what to say. "About me," I amended. "And Sunstreaker."

Prime's posture relaxed a little, and he folded his arms calmly over his chest.

"Yes?" he prompted after a few moments.

"We aren't twins," I blurted.

_Ooooh, nice and subtle_, he crooned.

Optimus Prime, meanwhile, was giving me a deeply quizzical look, or at least his posture shifted so that it conveyed puzzlement. And suddenly, I wanted nothing more than to leave the room. I was even backing, inch by uncertain, frightened inch, toward the door behind me. But something stayed me. Maybe it was Sunstreaker's amusement, his scathing amusement at his pathetic weaker half that was still coursing through me, encouraging me to quit while I was still marginally ahead. Perhaps it was his very encouragement to quit, to leave, to run away in shamed terror, that ultimately and perversely convinced me to stay, convinced me to stand my ground to the likely bitter end. Whatever it was, words suddenly came to me in a flood that vomited itself out of me before I could think about it, as if the words needed to leave me or else I would otherwise sicken and wither away into nothing. Less than nothing.

"I know…" I said quietly, hesitantly, to the floor, for I couldn't meet Optimus Prime's gaze, couldn't bring myself to do so. "I know that's what our records say, but it…it isn't the truth. It's…it's all a lie that Sunstreaker made up, long ago. The only thing…the only thing that's true about anything in our records is…is that we _are_ a split spark. But it… It didn't happen when we were created. It was…done to us. To me, and then I became an 'us.'"

The stream of mostly-stupid words abruptly halted when Sunstreaker laughed at me, when he made some biting, stinging comment that was lost to me because I was of a sudden concentrating solely on forcing myself to look up – way up – into Optimus Prime's face. His imposing and daunting shadow still fell across me, and confusion was still radiating from him, but it was a different sort of confusion now, focused on me and prompted by what I had been saying.

My gaze locked with Prime's, and I said, "For most of my life, _our_ life, he and I were one being, and the split, it… It happened much later and…and the procedure was flawed. _He, _or rather the part that became him…it wasn't supposed to survive, but it did, _he_ did, and then—"

Words died in my throat as Prime took an ominous, reverberating step toward me, and then loomed over me.

"What kind of 'procedure' takes a perfectly good spark and splits it in two?" he demanded to know, his voice low, rumbling in the way that it always rumbled when he was morally outraged about something. As if he was outraged on my behalf. As if I deserved pity or defense or anything other than…than death. But he still didn't know what I had done, suddenly thought me an innocent victim of….something. And he was leaning down toward me now, our gazes still locked, and of a sudden my nervousness vanished, replaced by resigned resolve. There was no going back now, and I would do well, I thought, to simply be done. With everything. As quickly as possible.

"The kind," I said softly but determinedly, "that's meant to 'rehabilitate' the worst kind of criminal that you can possibly imagine."

He recoiled from me, stared at me, and even his limited expression was stunned. I felt his surprise, too, felt it mutate into shock as my meaning occurred to him. Sunstreaker was quiet – too quiet, ominously quiet – but I couldn't spare a thought for him. The words were flowing again. I told Optimus Prime everything. I told him about the forty-four people that we – _I_ – had killed. I told him their names, for I remembered them all, took great pains to remember them. I told him of our methods, our reprehensible methods and the twisted, relentless reasoning that drove them. I told him of our capture, the trial…the sentence. I told him of the last-minute alternative that I now wished, fervently wished, that I had declined, and I told him what had happened as a result of it. I told him the truth, all of it in all its brutal glory, about who and what Sunstreaker and I were then…and what we were now. I told him of my long efforts to control him, and of the fact that, now, that was beyond my abilities.

When I was finished, when there were no more words, I was spent both mentally and physically. I found myself leaning against the wall behind me, shaking uncontrollably. The wall was quite literally holding me up, and I sank down against it, gratefully and pitifully, until I was sitting on the floor, hunched against it, cowering against it. I was still staring up at Optimus Prime, and he was still staring down at me, trying to absorb and to comprehend all that I had said.

"So…Bluestreak…" he managed to say, but he got no farther than that.

"He's trying to go back to what we were before we were split," I said wearily, my voice roughened with a combination of use, violent trembling, and emotion. "Since he's rather…severed himself from me, he really knows no other way to exist, so in a way he can't help it. But like me, he is…incomplete. More incomplete than I am. He needs someone to take over the role that I used to play, someone to replace the qualities that I have now. He needs someone who can plan. Calculate. Strategize. Someone who has the ability to look at people and situations with nothing but ruthless, emotionless logic."

Optimus Prime stared at me, absorbing what I'd said. It didn't take him long to realize my meaning, and when he did he turned wordlessly away from me and paced around Ratchet's desk to activate its embedded comm panel. Dimly, I heard him summon Prowl to Ratchet's office and, seconds later, Prowl stalked into the room, all perfect posture, gleaming armor, flaring doorwings, and barely-suppressed rage that battered at my weakened defenses. Even more dimly, I heard Optimus Prime quickly tell Prowl everything that I had just told him in a hushed voice, as if he was telling some secret that I didn't know.

"If he thinks that doing…doing that…to Bluestreak is going to endear me to him—" Prowl started to say, quietly outraged, as he turned toward me. He was closer to outwardly showing rage than I had ever seen him. The emotion pouring from him galvanized me.

"Not 'endear, Prowl," I interrupted quietly, but my words cut across the space between Prowl and me. I pushed myself up to my feet again and continued, "He's trying to remove from you anything and anyone who is familiar, anyone or anything that you care about or who cares about you. Once he's done that, once he's isolated you, he will…twist you, mold you into the individual that he wants you to be, so that he can use you. It's…what we always used to do."

Prowl frowned deeply at me, his brow furrowing uncertainly as he wrestled with what I'd said.

"I don't see how that would—"

"Of course you don't," I interrupted again, knowing what Prowl was about to say, "because it makes no logical sense…unless you're a sociopath. _Until_ you're a sociopath. So…You just have to trust me. Please, Prowl. Don't give him the opportunity to do this to you."

At that, Optimus Prime snorted. It was a sound rarely heard from him, and so whenever he did decide to make such a noise, all attention immediately settled on him, even when the audience was only two strong.

"Given what you've just told us, Sideswipe," Optimus Prime said quietly, devastatingly quietly, talking over whatever Prowl might have said to me, "why should we believe a word you say? About any of this? You've been lying to us for a very long time; that much at least is quite clear. So how do we know that you're not controlling Sunstreaker so that _he'll_ take the fall for something that _you're_ planning, for something that _you're_ in control of?"

_Told you so!_ Sunstreaker announced, the tone of his "voice" almost sing-song as it smirked and bubbled through my being, as I gaped up at Optimus Prime, stunned beyond words. And then my "brother" faded into silence again.

"Perhaps we need to hear Sunstreaker's side of this story," Optimus Prime said when he saw that I, stupidly gaping at him in mute disbelief, was going to say nothing. And then he was calling Ironhide, calmly telling him to bring Sunstreaker to a nearby conference room.

A few moments passed then, moments that I spent trying to figure how in the universe I was going to prove that I was telling the truth, especially when my competition was a compulsive and extremely talented liar, an extremely convincing actor. And then Ironhide's puzzled, hesitant voice floated over the comm.

"Uh…Prime?" he said.

"Go ahead," Prime answered levelly.

"We've got a slight problem here," Ironhide answered.

Optimus Prime glanced at me, as if he thought that I knew what the problem was. I could only shrug helplessly. For millions of years now, I had wanted nothing more than to be separate from Sunstreaker, to be freed from the burden of him. I had fervently prayed that we would one day be able to go our separate ways, safely. Now, I wanted nothing more than to be able to know exactly what Sunstreaker was up to. The irony was not lost on me.

"What is it?" Prime was asking of Ironhide, once he pulled his searching, questioning gaze away from me.

Cold dread gripped me like a vise as Ironhide's perplexed answer came over the comm and then dropped onto me like many kilotons of bricks dropped from a very great height.

"Sunstreaker ain't here, Prime," Ironhide reported. "He's…gone."


	4. Chapter 4

_OMG, I'm sooooooooo sorry this took so long! Personal life kind of blew apart...and then my laptop became ill. :P But to make it up to all of you...I give you all of the rest of the story in this chapter plus two more. Hope it's worth the wait, and thanks to everyone who's read/reviewed/faved/alerted/kumquat._

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_I'll disappear…And then I'll return_

_I'll disappear…And then I'll return._

The word, his words, rang in my head over and over again, an endless, droning litany, a promise of a bleak and blackened future. The words loomed so large in my consciousness that there was hardly room for anything else. Not the long, betrayed, questioning look that Optimus Prime leveled at me and for which I had no answer. Not the look that Prowl leveled at me, outwardly collected but inwardly enraged and perhaps just the slightest bit…afraid. Afraid that I was telling the truth. Or afraid that I wasn't.

_I'll disappear…And then I'll return._

_I'll disappear…And then I'll return._

The words largely drowned out what happened next, too. I was vaguely aware of Optimus Prime ordering search parties. Vaguely aware of myself whispering that they wouldn't find him, but that he would find them, if he wanted to. Vaguely aware of my warning being ignored, if it was heard at all. Vaguely aware of Prowl quietly arguing when Optimus Prime ordered him to stay with me, of him trying to mollify the tactician by telling him that if I was telling the truth, then he didn't want Sunstreaker getting within a hundred yards of him. Vaguely aware of Prowl's dutiful but frustrated acquiesce. Vaguely aware of Optimus Prime leaving Ratchet's office.

All of this happened as if it was happening far away and not to me. I witnessed it all numbly, separated from myself, mesmerized by the memory of his voice, as the words he'd said repeated in my mind in an infinite loop.

_I'll disappear…And then I'll return._

_I'll disappear…And then I'll return._

Every repetition of his words, his plan, his promise took on an increasingly sinister cast. Every repetition rang more loudly than the previous one had. Every repetition reminded me that I could do nothing to stop him. Nothing at all. It was all out of my hands, completely out of my control, perhaps my final penance or maybe just the latest one. I didn't think he'd let me go this easily. He had a goal in mind, a plan, but certainly that plan included a way to torment me, perhaps as payment for having kept him in check, against his will, for so many years. I was certain that he wasn't done with me and the certainty chilled me to my core.

_I'll disappear…And then I'll return._

_I'll disappear…And then I'll return._

_No_, I finally answered, the word a mere mental whisper drowned out by his insistence. _No_, I repeated, a little more loudly, then _No no no no no no…._Over and over again, rising in volume and hysteria with each repetition, until it was a desperate, piercing keen.

I had no idea that I had been screaming aloud, not until strong white hands gripped my shoulders, not until I was shaken violently. And even then I didn't stop, not until a steely, firm, commanding voice demanded that I control myself.

I blinked after that and the universe blinked with me, and the words, my own and Sunstreaker's, died. They faded into silence as I stared into Prowl's face, inches from mine. He who knew all about control, whose very life was control. I wished that I had a mere fraction of his strength, especially now that the source of mine, as awful as he was, was gone.

I stared at Prowl mutely, stupidly, frozen and paralyzed, and he held my stare for a long moment before he stepped away from me, perhaps distastefully. I continued to stare at him as he turned away from me, as he swept the clutter off of the seat of the chair behind Ratchet's desk with one swipe of his arm. I watched him approach me again, and I offered no resistance as he tugged me toward the cleared-off chair and sat me down in it. I gripped the arms of the chair as if I thought I might fall out of it otherwise, as if my life depended on it. And I watched at Prowl perched himself almost delicately on the one clutter-free corner of Ratchet's desk, his body turned toward me, arms folded under his chest, face impassive and yet somehow expectant at the same time.

I stared up at him, and I said, "I'm sorry. I'm so sorry, Prowl."

Prowl looked mildly surprised.

"For what?" he asked, his head tilted curiously to the side. Anger stilled roiled within him; I could feel it. But he controlled it beautifully, out of long practice. "If you're telling the truth," he pointed out, "then none of this is your fault."

"But it is," I insisted quietly, drained. "You don't understand."

His eyes narrowed at me, suspicion plain now where before it had been veiled. Controlled, along with everything else.

"Then perhaps you had better _make_ me understand," he said, his voice suddenly a threatening hiss as he leaned toward me in a way that was supremely menacing in one so otherwise controlled, both emotionally and physically.

And I tried to make him understand. I told him of my self-assigned mission to keep my "twin" under control, to channel his darkness toward a constructive purpose, namely destroying Decepticons. Told him of my attempts to divert his attention away from Prowl himself. Told him of the fact that he and his darkness were constants in my mind and my occasional need to escape from it all, just for a little while, which had ultimately allowed a disaster to occur.

Prowl still didn't really understand because no one could, but he did seem somewhat satisfied. As I spoke, his anger retreated, just a little, replaced in the forefront of his thoughts by puzzlement.

"Why didn't you say anything?" he wanted to know. "Why did…did _this_…have to happen before you opened your mouth?"

Even as controlled as he was, the pain that he was feeling bled into his question. The agony cut into me and then it seeped into the resulting wound.

I looked Prowl square in the face and said, "Because I'm a coward. Haven't you figured that out yet? You think it would be easy to go up to Optimus Prime or to you or to _anyone_ and say, 'Hey, guess what?' after living this lie for long? I didn't have the strength for that. I like being…liked. At least, now I do."

"But you knew that something like this could happen," Prowl observed, unmoved. It wasn't' a question.

"Yes," I answered dismally.

"You _are_ a coward, then," Prowl decided, disgust in his voice.

I met his gaze miserably.

"Yes," I repeated. "But at least now I have nothing left to be afraid of."

"You think so?" Prowl asked, his voice flat and his expression suddenly as cold as outer space. Again, it wasn't really a question.

And then he drew his weapon. My halved spark pulsed harder, faster as I watched him raise it. But ultimately, he didn't point it at me.

"Tell me, Sideswipe," he said, almost distractedly, although I knew that was virtually impossible for him to be distracted. He traced the simple, utilitarian lines of his weapon almost fondly as he continued, "What would happen to Sunstreaker if you were to die?"

I fought back the whimper that wanted to explode from my throat. I was a coward, indeed. Especially without him. I was certain that Prowl could hear the frantic pounding of my spark as I answered, "I don't know for sure. No one does. He might die, too. He might not."

Prowl nodded at that, didn't look at me, not for a moment. When he did look at me, his gaze was diamond-hard, his face utterly expressionless. He laid his gun casually across his lap and then asked, "What if you were just hurt?"

I flinched at the question because I knew the answer to it.

"He would feel it," I answered quietly. "But over the years we've both learned to block it somewhat. And he's better at doing that than I am."

"So you would have to be hurt badly for it to affect him?" Prowl concluded dispassionately. And even I could no longer sense what he was feeling beneath the surface. He was completely controlled now, his mind apparently chewing on a plan, as was its wont, and the chewing as usual blotted out all else.

I swallowed nervously, afraid of Prowl's dispassion. It fleetingly occurred to me that I was, as the saying went, getting a taste of my own medicine; I used to toy with people in exactly the same way. Now I was experiencing first-hand the terror that such toying could evoke. I didn't like it. More guilt loaded itself onto my shoulders, on behalf of those long-ago victims.

Except that I knew that Prowl didn't toy. He reasoned. Coldly. Logically. In his mind, efficiency sometimes trumped abstract concepts like right and wrong. It was exactly this that would make him vulnerable to manipulation, should Sunstreaker's plan, whatever it was, succeed. It was exactly this that made Prowl potentially very dangerous.

And he was looking at me now, expecting me to answer him, wanting me to confirm that inflicting massive amounts of pain on me would have an effect on Sunstreaker. I gathered my non-existent courage and answered in the affirmative. Quietly. My voice wavered pitifully around the single word. Prowl merely nodded calmly, filing the information away.

"Well," he said, concluding his reasoning, "I suppose we first see how well the search parties do. If they don't succeed, perhaps we shall employ a…different method of locating Sunstreaker."


	5. Chapter 5

As it turned out, one of the search parties did very well. It was the one led by Jazz, and when I heard that…the news hit me like a ton of bricks. I knew what it meant. I leaned back in the chair in which I was sitting, closed my eyes, and moaned a prayerful, "No."

Prowl did not generally deign to have friends. It was commonly known that he considered them a distraction, and it was commonly though erroneously believed that he was emotionally incapable of having them. I knew better, knew that he simply considered the concept of friendship a threat. I didn't know why he had this fear; I only knew that it existed. I also knew that he had chinks in his armor.

So did Jazz, who also believed that no one was or should be an island. He seemed to have made it a personal mission to widen the chinks in Prowl's armor, and he had surprisingly had some measure of success, much to Prowl's chagrin. The upshot was that Prowl considered Jazz a friend, now.

And this, of course, put Jazz in danger, now. And Prowl knew it, or at least was beginning to suspect it, now. I suspected that we all made it through this mess, Prowl would laboriously mend his armor chinks and no one would touch him again.

Prowl had been pacing as he'd listened to the search parties' progress on the comm channels. When Jazz had reported that they'd located Sunstreaker, and when he heard my reaction to the news, he paused abruptly in mid-stride. Our gazes locked as Jazz talked to Sunstreaker in the background and Sunstreaker answered, all innocuous charm. We stared at each other for what seemed like minutes but that was probably only a few seconds…

…Until Jazz uttered a surprised, "Hey what the —?" and the comm channel went suddenly and ominously dead.

Prowl exploded into a flurry of movement, stalking around Ratchet's desk and yanking me out of Ratchet's chair and to my feet.

"Let's go," he said, heading for the door with me in tow, his grip around my arm like a vise. I tried to dig in my heels, pointed out that Optimus Prime had ordered him to stay put. He merely growled a surly, "I don't care" as the medbay doors slid closed behind us. "This ends now," Prowl declared coldly as he stalked down the corridor.

We were almost there when we heard a strangled noise close-by: Jazz, trying not to scream, and there was fear in the sound. Not much frightened Jazz. Years in Special Ops saw to that. He hadn't known what he was up against, though. There hadn't been time for such a briefing even if Optimus Prime had fully believed what I'd told him. Jazz had been taken by surprise. By a "friend."

Prowl and I rounded a corner, and there they were. With one hand, Sunstreaker held Jazz's own gun to Jazz's head. Normally, Jazz could and would have maneuvered himself out of such a position easily. But Sunstreaker's other hand held a short energon blade that he'd acquired somewhere after he'd escaped his cell. The blade was sunk into Jazz's chest, directly over his spark. It wasn't lodged deeply enough to kill him, but it was clear that if Jazz made a move that Sunstreaker didn't like, Sunstreaker would be all too happy to drive the blade home. Even as we watched, Jazz twitched involuntarily…and the blade sank a bit deeper. Pain lanced across the saboteur's face, but he forced himself still and silent.

Sunstreaker, meanwhile, favored Prowl with a wide, genuinely happy smile.

"Prowl!" he crowed. "So good of you to join us! Thought you might. And you brought my favorite brother, too! How thoughtful of you."

"Let him go, Sunstreaker," Prowl demanded, his voice menacing and his weapon leveled unerringly at Sunstreaker's head.

"Oh, don't worry yourself. I will!" Sunstreaker airily assured him. "Eventually. First, you and I need to have a talk."

"Fine," Prowl agreed shortly. "Talk." At the same time, Sunstreaker projected at me, _Isn't this fun, hero man?_ I merely scowled in return.

"Here's the deal," Sunstreaker said aloud to Prowl. "You, me, Jazz, and my 'dear' brother there are going to take a little trip. If you all behave yourselves, then Jazz will eventually come back here. If not…" He smiled sweetly, beautifully angelic…and the blade sank a few inches farther into Jazz's chest. Jazz bit down into his lip to stave off a scream, all the while leveling a warning stare at Prowl that clearly said, "Don't you dare agree!"

Prowl lowered his weapon then, appearing to consider Sunstreaker's proposal. When I opened my mouth to protest, he merely tightened his grip around my arm to somewhat painful levels, silencing me. Then almost casually, his weapon still lowered, he strode toward Sunstreaker and Jazz, taking me with him. The other members of Jazz's search party, who'd stood between us and Sunstreaker, parted before us in order to avoid being shoved aside. Prowl halted just a few paces away from Sunstreaker.

"We'll be going where?" he asked mildly, calmly.

"Away from here," Sunstreaker answered. "That's all you need to know."

"And if Sideswipe and I are cooperative," Prowl continued equably, "you'll let Jazz go."

"Yes," Sunstreaker hissed impatiently.

"How do I know you'll keep your word?" Prowl persisted, unmoved by Sunstreaker's impatience.

"Oh, you're just going to have to trust me."

I snorted at that. Sunstreaker turned his head toward me and then, smiling that sweet smile again, pushed the blade another inch into Jazz's chest. Prowl shot me a warning glare as Jazz, unable to hold it back, let out a yelp of pain. The blade was deep enough now to be doing some serious damage.

"So what do you say, Prowl? You could use a vacation. It'll be fun!"

Prowl was quiet for an almost indecently long time. He was calculating probabilities, no doubt. When he was finished, he leveled a cool gaze on Sunstreaker.

"As appealing as it sounds," he said at length, "I'm afraid that I'll have to decline."

And then, lightning-quick, he spun toward me, weapon raised.

Prowl's gaze locked with mine, and for the briefest instant, a mere split-second, there was eloquent but unspoken apology there. There was an unexpected and soft empathy in his eyes, in the lines of his dark face. There was regret for doing what he knew – and what I knew – had to be done, the only thing that could be done to save Jazz without putting him in any further danger. And then it was gone, all gone. The mask dropped down over Prowl's expression, hardening it to impervious dark grey granite. The gleaming barrel of his rifle was leveled unwaveringly on me, and I stared at it, strangely fascinated by the way that the light played over Prowl's weapon for the few fractions of a second that elapsed before he fired it.

Point-blank. Repeatedly.

I could do nothing to dodge the blasts, wouldn't have done anything even if it had been within my power to do so. Instead, I welcomed them, let them impact me. Consume me. Embrace me. I felt nothing but relief that this, all of this, the entirety of my twisted existence, would soon be over. If I could have, I would have thanked Prowl, but it was far too late for that.

Bright, flaring whiteness spread across my consciousness as vast amounts of energy surged and sizzled its way through me. Vital systems crashed left and right, just ahead of the devastating tide, trying vainly to protect themselves. Warnings flared across my diagnostics, as if I could do anything at all about them, as if I had any desire to heed them. Time seemed to stretch, milliseconds morphing into hours. Each pulse of my spark, every intake of breath, seemed to last an eternity. There was a curious and surprising lack of pain…and then the whiteness began to change, to shimmer, and then to darken. It slowly worked its way through ever-deepening shades of grey as I staggered backward under the force of the blasts. I collided with the wall next to me with a wordless grunt and with enough force to ricochet forward again. I fell hard and gracelessly to my hands and knees before collapsing entirely to the floor, face first and entirely numb.

Complete blackness enveloped me and then tugged at me, insistently pulling me down into some place that was utterly lightless and frightening, fraught with the unknown. But it was also warm. Without guilt. Without suffering.

I heard Sunstreaker unleash a furious roar, but the sound seemed muffled and very far away to me. I knew that he was howling with the fury of being thwarted and then that he was screeching with all of the agony that I didn't feel. But that knowledge didn't touch me, didn't affect me. Rather, I felt only satisfaction, but only for a very brief and piercing moment of serene and peaceful clarity.

And then I felt nothing and knew no more.

* * *

_So, this was the original end of the story, all of this story having been written while I was in a pretty deep pit of depression. And yes, just so that there's no confusion here, both Sideswipe and Sunstreaker are supposed to be dead. And I suppose that makes this story entirely AU, yes, though I didn't want to say that before. ;) So, if you prefer dark-with-a-tragic-ending and are OK with "totally AU," then you need read no farther. This is "The End."_

_BUT! Now that I'm not quite in such a depressive state, I decided that I might want to play around with this whole idea a bit more, so I wrote one more part. It makes some things not quite so…final. But reading it is entirely optional; if you prefer dark, tragic, and done, don't read it. You won't miss anything except me opening up the possibility of A) playing with this concept a bit more and B) torturing poor Sideswipe some more because, you know, I must torture those whom I love, and I have come to love this Sideswipe. ;) But if you do want to read it… Well, the "epilogue" will be up in a moment. __:) _


	6. Epilogue

I was floating in a void. All was blackness and for a long time, silence. But then there were voices. Just a few here and there, at first. Faint. Distant. I thought that I should recognize the voices, but I didn't, not really, and I sank into the void again…

"He'll come around when he's damned good and ready," a gruff voice said some indeterminate time later, pulling me up from the depths again. "Hovering isn't going to make it happen faster," the same voice continued. "Shoo!"

I concentrated on the voice. I knew who had spoken, knew his name. It hovered, shimmering in my consciousness, just out of my reach. I wanted to growl in frustration, but I didn't seem to know how to make my voice work.

"Just relax, Sideswipe," the voice said, apparently talking to me. "You've been in stasis for a while, and it'll take a while to come out of it."

I could do nothing but obey the voice, and I let the void embrace me again.

When I awoke again, when I could open my eyes, the first bleary though that occurred to me was that the Ark and the Pit had identical orange ceilings. But that didn't make sense. I shook my head to clear it out, and in response, the universe inverted and lurched into a stuttering, nauseating spin. I must have made some sort of sound in response because Ratchet – That was his name! – suddenly materialized next to me. He said something to me, but I couldn't quite catch what he said. I was too busy trying to make the universe hold still. Eventually, after a small eternity, it settled, and I looked up at Ratchet.

"Wha…?" I asked intelligently, and that was as far as I got. Words formed in my processors easily enough; getting them to come out of my mouth seemed to be the tricky part.

Ratchet, somehow knowing was I was going to ask, filled me in.

"You've been in stasis for about six months, on Optimus Prime's orders. Took him that long to figure out what the hell to do with you."

"Should have let me die," I muttered.

"Yes, that would likely have been a lot easier for you, wouldn't it?"

There was an edge to his voice. Ratchet was often grumpy, but much of it I knew to be an act, his own special brand of defense mechanism. But this wasn't an act; he wasn't entirely happy to see me awake.

And so it began…

"Did some research while you were out," Ratchet was saying meanwhile. "Records are sketchy, but we did find some court documents and a notation that you'd been remanded to some experimental rehabilitation program. So that checked out."

I nodded but kept silent, so he continued.

"And then Jazz did some digging and somehow managed to find some of the program's records. Some of them talked about you, so…Optimus decided to bring you around."

Only one word of what he'd said really leapt out at me.

"Jazz is all right," I breathed, relieved.

"He's fine," Ratchet confirmed. "Sunstreaker did some more damage after Prowl pulled his little stunt, but I pulled him through. Bluestreak's OK, too." He paused significantly and then added, "Physically."

Dread, guilt, and remorse pounced on me, and I could do nothing to defend myself against their assault. I closed my eyes in surrender.

"Dear Primus help me," I murmured prayerfully.

"Mmmm," Ratchet grunted in apparent agreement. "Indeed. Sunstreaker's also in stasis," he informed me, "although he'll be staying there unless some miraculous and _real_ method of rehabilitating him happens along."

It was only as Ratchet said the words that I realized that I was alone, truly alone as I had never been since…since I had existed in this form. There was a only a hollow, ringing emptiness where he had once been, and I felt more incomplete than ever. I was alone, incomplete…and I had to live amongst a few dozen Autobots who probably hated me and rightfully so. Worst of all, I would be able to feel their anger, their hatred. The thought was overwhelming. Terrifying.

"Ratchet, I can't do this," I whispered, stricken. "Put me back in stasis. Please. Or kill me. Something, _anything_ other than this."

Ratchet laughed. For a long time.

"Oh, no," he said when he calmed down. "This is your punishment, you see. And you _can_ do it. Or at least you _will_ do it. You have no other choice. Death is easy. Living…not so much."

"But that's—" I began to protest.

"Don't you _dare_ say that it's cruel," Ratchet interrupted, leaning over me threateningly. He was genuinely angry only infrequently. Now, he was utterly furious. "We _know_ what you did. Found those records, too."

I could only stare at him, wide-eyed, and I couldn't stop myself from trembling violently. I had no idea what to say.

Ratchet snorted at me contemptuously, and then he turned away and headed for the door of the small, private, and no doubt guarded and monitored room that I occupied.

"Better rest up," he tossed over his shoulder. "Tomorrow's the first day of the rest of your life."

And then he was gone. And he was right, too. The first day of the rest of my life. The only problem was that it was a life I was certain I didn't want to live because I had simply exchanged one monkey on my back for another.

* * *

_So there you go! I might write more stories after this. I don't know. It depends on how the mood strikes me. I have other things I need to finish, though. Thanks for reading and, if you've been waiting for this conclusion, thanks for your patience. :)_


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